The spectrum of performing styles for Bach's B minor Mass has become very wide. At one extreme there is still the traditional choral-society approach, with five soloists, a large choir and an orchestra to match, at the other is the still controversial minimalist treatment pioneered by Joshua Rifkin in the 1980s, that uses just eight singers, one to each part. Rifkin published his edition of the score in 2006, which for the first time presented the work as Bach left it in 1750, and John Butt and the Dunedin Consort are the first to use it as the basis of a recording. Butt uses 10 singers—five soloists, reinforced by five of what he calls "ripienists" whom he adds and subtracts as the textures suggest in the choruses—together with an orchestra of 19 players. It's a performance full of air and lightness; the instrumental textures have a springing, dancing vitality, the voices are perfectly focused, and agile. Just occasionally, as in the eight-part passages of the Credo, for instance, a bit more weight of choral tone might define things more clearly, but overall this is a fascinating and hugely rewarding account of one of the imperishable masterpieces of the western musical tradition.